Development documentation

This describes Keydra as it is being built and is not a released version. What it documents can change before a release.

Reading and editing values

An editor per type, loaded in segments so a large value is opened rather than downloaded, and a decoder chain that reads what was stored.

Reading and changing values#

Each of the server’s types has an editor of its own, and each loads in segments rather than all at once — HSCAN, SSCAN and ZSCAN for the scanning types, windows of LRANGE for lists, pages of XRANGE for streams. A large value is opened rather than downloaded.

A hash open beside the key list, with its fields and values editable in place

String: One editor, with an Encoding selector.
Hash: A Field and Value table with inline editing, New field name and New field value to add one, and a delete action per row.
List: An Index and Value table. New elements go to the Head or the Tail.
Set: A Member table, with New member.
Sorted set: Member and Score, both editable.
Stream: A viewer, paged.

A value that is too large to return#

Some values cannot be returned whole. Keydra shows the beginning and marks the value Shown in part, with the explanation that it cannot be edited or copied from here without overwriting the rest. Copying is refused for the same reason: it would produce something shorter than what is stored.

Copying a value out#

The key’s actions offer Copy key name, Copy as JSON and Copy as redis-cli command. The last is the one that makes a value portable into a terminal or a script.

Encodings Keydra can decode#

The Encoding selector defaults to Automatic, which lets the server detect the format. Choosing one explicitly is for the cases where the guess is wrong or where a value could plausibly be read two ways.

Name Description

Name	Description
`Base64`	Base64-encoded content, decoded and then offered to the rest of the chain.
`Brotli`	Brotli-compressed content. Guessed last and under conditions, because Brotli carries no header to recognize it by.
`Deflate`	Raw deflate, without the gzip wrapper.
`Gzip`	Gzip-compressed content. Announces itself with a magic number, so the guess is safe.
`Hex`	Bytes as hexadecimal, for values that are not text at all.
`JavaSerialized`	Java serialization. Described rather than deserialized: turning it back into an object means running code the value chooses.
`Json`	Recognised as JSON and shown formatted. The commonest thing a string holds.
`Lz4`	LZ4-compressed content.
`MsgPack`	MessagePack, decoded into a readable structure.
`PhpSerialized`	PHP’s `serialize()` output, unpacked into a readable structure.
`Pickle`	Python pickle. Described rather than unpickled, for the same reason as Java serialization.
`Plain`	The bytes as they are, decoded as UTF-8 text. What most values are, and the last thing tried.
`Protobuf`	Protocol Buffers, shown as the field numbers and wire types the bytes actually contain — no schema is available, so the field names are not.
`Zstd`	Zstandard-compressed content.

Base64

Base64-encoded content, decoded and then offered to the rest of the chain.

Brotli

Brotli-compressed content. Guessed last and under conditions, because Brotli carries no header to recognize it by.

Deflate

Raw deflate, without the gzip wrapper.

Gzip

Gzip-compressed content. Announces itself with a magic number, so the guess is safe.

Hex

Bytes as hexadecimal, for values that are not text at all.

JavaSerialized

Java serialization. Described rather than deserialized: turning it back into an object means running code the value chooses.

Json

Recognised as JSON and shown formatted. The commonest thing a string holds.

Lz4

LZ4-compressed content.

MsgPack

MessagePack, decoded into a readable structure.

PhpSerialized

PHP’s serialize() output, unpacked into a readable structure.

Pickle

Python pickle. Described rather than unpickled, for the same reason as Java serialization.

Plain

The bytes as they are, decoded as UTF-8 text. What most values are, and the last thing tried.

Protobuf

Protocol Buffers, shown as the field numbers and wire types the bytes actually contain — no schema is available, so the field names are not.

Zstd

Zstandard-compressed content.

Decoding is a view, not a change

Decoding happens on the server when the value is read, and changes nothing on the target. What is stored stays exactly as it was.

Brotli is guessed last, and cautiously

Brotli announces itself in no way at all — it has no magic bytes. Its guess is fenced: it is tried last before plain text, the stored value must look like bytes, and what comes out must be printable and larger than what went in. Anything else and the value is shown as it is.

Java serialization and Python pickle are described rather than deserialized. Turning either back into an object means running code the value chooses, which is a remote code execution primitive rather than a feature.

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